Persistent Organic Pollutants, Landfill Leachate Sampling Study

Summary: Numerous hazardous substances have been detected in landfill leachate including certain persistent organic pollutants (POPs), which can pose a serious risk to human health and the environment. The Environmental Protection Agency (EPA) commissioned a study to investigate landfill leachate for a range of POPs and other hazardous chemicals and to assess the disposal routes and management of the leachate.

POPs landfill leachate sampling study thumbnail

Published: 2021

Pages: 95

Filesize: 6,855 KB

Format: pdf


Six landfills were included in the study, three operational (accepting waste at the time of the study), and three historic (ceased accepting waste at the time of the study and were closed or in an aftercare program), five of which were lined landfillsInformation was gathered from site personnel during phone interviews and site visits including information on leachate systems and disposal routes. Twenty-four test samples were obtained from the landfills including 17 leachate (from leachate holding tanks/lagoons and leachate pump systems)six groundwater monitoring and one surface water sample, as well as six quality control samples (three duplicates and three equipment rinsates). All samples were analysed for POPsper- and poly-fluoroalkyl substances (PFAS)metals and metalloidsphenols and cresols, phthalates and organochlorine pesticides. 

All chemicals analysed were detected in samples from two or more sites, with PFAS in particular being detected at all sites and in all test samplesInformation gathered from each site revealed that leachate from the five lined landfills is disposed of via wastewater treatment plants (WWTPs), either transported from the landfill to the Ringsend WWTP, or, for one site, released into sewers leading to the Newbridge WWTP 

This report highlights the variety and levels of hazardous chemicals that can be found in landfill leachate. Further assessment of the leachate disposal routes is required to consider if WWTPs are equipped to remove these substances and mitigate the risk to human health and the wider environment either directly from discharge from WWTPs to waterways, or, indirectly from the application of sludge to agricultural land.